Quick-acting clamp



Dec. 23, 1952 l.. J. RoussJE/Au QUICK-ACTING CLAMP Filed March 25, 1948 ll.. IIA.. .J

JNVENTOR. ,Zo .foassecza/ BY #57M from a fixed jaw 2l.

Patented Dec. 23, 1952 UNITED QUICK-ACTING CLAMP Leo J. Rousseau, Grosse Pointe, Mich., assignor to Minit-Man, Inc., Detroit, Mich., a corporation of Michigan Application March 25, 1948, Serial N0. 16,990

Claims.

This invention relates to clamping devices and in particular to quick-acting clamps.

One object of this invention is to provide a quick-acting clamp which is especially adapted to be rapidly engaged with or disengaged from a chain, such as a conveyor chain, so as to initiate or terminate the motion between the load being conveyed and the conveyor chain in a rapid and eioient manner.

Another object is to provide a quick-acting clamp adapted to instantly release its grip upon a chain in response to the shifting of a locking plunger, either manually or by engagement with a fixed abutment such as a stop.

Another object is to provide a quick-acting clamp which is positioned above a chain, such as a conveyor chain, where it is easily accessible to an operator and which has chain-engaging jaws extending downward from the main portion of the clamp.

In the drawings:

Figure 1 is a top plan view of a quick-acting chain clamp according to a preferred form of the invention, with the parts in their chainengaging position;

Figure 2 is a side elevation of the chain clamp shown in Figure l;

Figure 3` is a vertical section, mainly in end elevation, of the chain clamp shown in Figures l and 2 taken along the line 3--3 in Figure 2;

Figure 4 is a vertical section taken along the line 4-4 in Figure l;

Figure 5 is a horizontal section taken along the line 5-5 in Figure 2;

Figure 6 is a top plan view, partly in section,

of the chain clamp shown in Figure l, with the parts in their chain-releasing position; and

Figure 7 is a fragmentary longitudinal section taken along the line 'E--l in Figure 1.

Referring to the drawings in detail, Figures l, 2 and 3 show a quick-acting chain grab or clamp generally designated lo according to a preferred form of the invention, as consisting of a housing or base structure formed from a pair of upper and lower plates i3 and It (Figure e) of L-shaped cross-section with side wall portions $5 and it and welded together as at ll. Extend-- ing downward from the forward end of the upper plate i3 is a fixed jaw support i3 having a transverse hole it which serves as an anchorage for the stem 2Q (Figures 5 and 6) extending laterally The latter is preferably of bronze and is mounted in this manner in order to be easily replaceable after excessive wear has occurred. The outer end of the hole IS is iiared and the stemy 29 correspondingly enlarged to securely anchor the jaw 2| to the jaw support IB. The xed jaw 2l is provided with a notch-like recess or chain link socket 22 rounded at its forward end to receive and nt the forward end of the link L of a chain C.

Opposing the iixed jaw 2l is a similar movable jaw 23 having a similar recess or chain link socket 2li engageable with the opposite side of the chain link L and having a similar stem 25 anchored in a transverse hole 26 in a movable jaw support 27. The hole 26 is flared at its outer end and the outer end of the stem 25 enlarged to nt the flared portion to provide a secure anchorage. The movable jaw support 2l extends downward from a pivoted bar or arm 28 which is mounted in the elongated chamber 2S (Figure 4) enclosed between the upper and lower plates I3 and l These are provided with aligned vertical holes 30- and 3l in which is mounted a pivot pin 32 which also passes through a hole 33 in the bar 28.

The rearward end of the bar 28 is provided with a U-shaped locking notch 34 which is adapted to be engaged by the downwardlyturned end 35 of an L-shaped plunger or locking rod 36 having a horizontal portion 3l extending forward through a tunnel-like housing 38 welded as at 39 to the upper surface of the upper plate i3. The forward end of the rod or plunger 36 terminates in a circular head or collar de and a coil compression spring 4I encircling the forward end of the rod 35 constantly urges the head All and rod 36 to the left into its locking position with the rearward and bent end 35 in the locking notch 34 of the bar 2t. The downturned end 35 of the rod 3E is reciprocable in aligned longitudinal slots 42 and 43 in the upper and lower plates I3 and lll respectively,

The movable jaw support 2 is constantly urged toward its open or releasingY position by a coil tension spring 44 having its rearward end anchored to a pin 45 seated in aligned holes 46 and lil in the upper and lower plates I3 and I4 and with its forward end anchored to a hook 48 welded or otherwise suitably secured to the jaw support 2l (Figures l and 6). The upper plate I3 is provided with a rearward extension 9 (Figure 7) overhanging the lower plate It and having a vertical hole 5) therein for receiving a link 5| of a chain 52. Connected to the rearward end of the chain 52 is the eye `53 of a hook 5i (Figure 1).

In the operation of the invention, let it be assumed that the clamp Il) and chain C are coupled as shown in Figures 1 to 5 inclusive. In

this position, the movable jaw support 21 is swung inward until its jaw 23 engages a link of the chain `C which is already engaged with the iixed jaw 2l of the fixed jaw support I8 (Figure In this position, the head 40 and the locking rod or plunger 35 are urged forward (to the left in Figures l and 2) by the coil spring 4|, forcing the downturned end 35 of the locking plunger or rod 36 into the locking notch 34 in the rearward end of the bar portion 28 of the movable jaw support 21. In this position of the parts, the coil spring 44 is under tension.

'Io release the clamp IU from engagement with the chain C, the head 40 is pushed rearwardly (to the right) either manually by a workman or by engagement with a stop either fixed or movable (not shown). As the rod 36 and its downturned end 35 move rearwardly in the elongated slots 42 and 43 (Figures 6 and 7) the downturned end 35 moves out of the notch 34 (Figure 6). When this occurs, the coil spring 44 comes into operation to swing the movable jaw support 21 around the pivot pin 32, releasing the movable jaw 23 from engagement with the link L of the chain C.

After uncoupling has thus occurred, the downturned portion 35 comes to rest against the rearward end of the bar portion 28 which is rounded as at 55 to facilitate this action. The engagement of the rod portion 35 with the rounded portion 55 under the urge of the coil spring 4 I, maintains the movable jaw support 21 in its swung out position of Figure 6. Thus, the load, such as a vehicle, being towed by the chain C and connected to the hook 54 comes to a halt, whereas the chain C can continue moving without interruption.

To recouple the clamp I to the chain C, the operator merely swings the movable jaw support 21 inward until it engages a link L of the chain C and forces this into the opposed recesses 22 and 24 of the jaws 2| and 23 (Figure 5). When this occurs, the rod 36 is free to move forward under the urge of the coil spring 4I, causing its downturned end 35 to enter the locking notch 34 and lock the movable jaw support 21 in the position shown in Figures l to 5 inclusive. Thus, the `clamp I0 may be instantly coupled to or uncoupled from a chain in a rapid and efcient manner. The recesses 22 and 24 are, of course, shaped to conform to the shape of the chain link L.

What I claim is:

l. A quick-acting chain grab for a towing load, comprising a base structure having a xed jaw supporting portion projecting laterally therefrom, a pivot element on said base structure, an arm pivotally mounted on said pivot element and having a movable jaw supporting portion projecting laterally therefrom adjacent said base structure jaw supporting portion, a pair of cooperating xed and movable chain grab jaws secured respectively to said fixed and movable jaw supporting portions, said jaws having opposed chain link sockets facing one another and shaped to receive the opposite sides of a chain link, said arm and movable jaw being swingable around said pivot element toward and away from said fixed jaw into closed and open positions of said jaws, a towing member secured at one end to said base structure and having at its other end an attachment element adapted to be secured to the load to be towed, said chain link sockets being disposed co-directionally with the axis of said towing member whereby to position the chain held thereby in the same direction as said towing member, and

a locking device mounted on said base structure and movable into locking engagement with said arm in the closed positions of said jaws.

2. A quick-acting chain grab for towing a load, comprising a base structure having a fixed jaw supporting portion projecting laterally therefrom, a pivot element on said base structure, an arm pivotally mounted on said pivot element and having a movable jaw supporting portion projecting laterally therefrom adjacent said base structure jaw supporting portion, a pair of cooperating fixed and movable chain grab jaws secured respectively to said fixed and movable jaw supporting portions, said jaws having opposed chain link sockets facing one another and shaped to receive the opposite sides of a chain link, said arm and movable jaw being swingable around said pivot element toward and away from said fixed jaw into closed and open positions of said jaws, a towing member secured at one end to said base structure and having at its other end an attachment element adapted to be secured to the load to be towed, said chain link sockets being disposed codirectionally with the axis of said towing member whereby to position the chain held thereby in the same direction as said towing member, said arm having a locking recess therein, and a locking member movably mounted on said base structure and movable into said recess in the closed positions of said jaws.

3. A quick-acting chain grab for towing a load, comprising a base structure having a fixed jaw supporting portion projecting laterally therefrom, a pivot element on said base structure, an arm pivotally mounted on said pivot element and having a movable jaw supporting portion projecting laterally therefrom adjacent said base structure jaw supporting portion, a pair of cooperating xed and movable chain grab jaws secured respectively to said fixed and movable jaw supporting portions, said jaws having opposed chain link sockets facing one another and shaped to receive the opposite sides of a chain link, said arm and movable jaw being swingable around said pivot element toward and away from said xed jaw into closed and open positions of said jaws, a towing member secured at one end to said base structure and having at its other end an attachment element adapted to be secured to the load to be towed, said chain link sockets being disposed co-directionally with the axis of said towing member whereby to position the chain held thereby in the same direction as said towing member, said arm having a portion extending rearwardly from said pivot element on the opposite side thereof from said jaws, said extension having a locking recess therein, and a locking member movably mounted on said base structure and movable into said recess in the closed positions of said jaws.

4. A quick-acting chain grab for towing a load, comprising a base structure having a fixed jaw supporting portion projecting laterally therefrom, a pivot element on said base structure, an arm pivotally mounted on said pivot element and having a movable jaw supporting portion projecting laterally therefrom adjacent said base structure jaw supporting portion, a pair of cooperating xed and movable chain grab jaws secured respec- .tively to said fixed and movable jaw supporting portions, said jaws having opposed chain link sockets facing one another and shaped to receive the opposite sides of a chain link, said arm and movable jaw being swingable around said pivot element toward and away from said fixed jaw into closed and open positions of said jaws, a towing member secured at one end to said base structure and having at its other end an attachment element adapted to be secured to the load to be towed, said chain link sockets being disposed co-directionally with the axis of said towing member whereby to position the chain held thereby in the same direction as said towing member, said arm having a locking recess therein,

and a locking plunger reciprocably mounted on said base structure and having a portion thereof movable into said recess in the closed positions of said jaws.

5. A quick-acting chain grab for towing a load, comprising a base structure having a fixed jaw supporting portion projecting laterally therefrom, a pivot element on said base structure, an arm pivotally mounted on said pivot element and having a movable jaw supporting portion projecting laterally therefrom adjacent said base structure jaw supporting portion, a pair of cooperating fixed and movable chain grab jaws secured respectively to said Xed and movable jaw supporting portions, said jaws having opposed chain link sockets facing one another and shaped to f.

receive the opposite sides of a chain link, said arm and movable jaw being swingable around said pivot element toward and away from said fixed jaw into closed and open positions of said jaws, a towing member secured at one end to said base structure and having at its other end an attachment element adapted to be secured to the load to be towed, said arm having a locking recess therein, a locking plunger reciprocably mounted on said base structure and having a portion thereof movable into said recess in the closed positions of said jaws, said chain link sockets being disposed co-directionally with the axis of said towing member whereby to position the chain held thereby in the same direction as said towing member, said plunger having a contact portion projecting forwardly from said base structure, and a resilient element yieldingly urging said plunger toward its locking position.

LEO J. ROUSSEAU.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 39,335 Beckman July 28, 1863 `512,543 Froberg Jan. 9, 1894 662,700 Sheppard Nov. 27, 1900 720,256 Kleinschmidt Feb. 10, 1903 730,038 Murlless June 2, 1903 1,051,230 Holman Jan. 21, 1913 1,280,163 Clarkson Oct. 1, 1918 1,440,991 Harrison June 2, 1923 1,734,072 Blalack Nov. 5, 1929 FOREIGN PATENTS Number Country Date 640,696 Germany Jan. 11, 1937 

